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1.
Am J Speech Lang Pathol ; 33(3): 1226-1235, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38329991

RESUMO

PURPOSE: Therapeutic bottle feeding is a critical skill for speech-language pathologists (SLPs) managing the increasing and medically complex neonatal intensive care unit (NICU) and early intervention caseloads. Thus, we explored the role of a high-emotion preterm simulator, known as "Paul," to increase knowledge, skills, and confidence related to infant feeding management for speech-language pathology graduate students. METHOD: A randomized controlled study compared learning outcomes of 27 participants following either a 1-hr lecture or 1-hr training with a preterm simulator. Outcomes included knowledge demonstrated on written examination, accuracy in identifying stress cues during simulated feeding, and self-reported anxiety levels related to clinically assessing infant feeding. RESULTS: No baseline group differences were found on written examination or during a simulated bottle feeding. Both groups improved in written examination scores and identification of stress cues (p < .001). Gains in written examination scores did not significantly differ between groups; however, after training, the simulator group correctly identified more stress cues during a simulated bottle feeding (p < .001), and the lecture group reported reduced anxiety related to clinically evaluating infant feeding compared to simulator-trained students (p < .05). CONCLUSIONS: All students demonstrated gains in written knowledge and identification of stress cues; however, simulation-based training was superior in developing the feeders' ability to identify stress cues during a hands-on simulated bottle-feeding scenario. Lecture-based training may have inflated students' perceptions in their clinical skills as they were less accurate in identifying stress cues during a simulated feeding but reported significantly reduced anxiety for administering a clinical evaluation of infant feeding compared to simulation-trained students. Hands-on training using high-fidelity simulation may capitalize on experiential learning to better build clinical feeding skills for future SLPs who may serve in NICU and early intervention settings, while eliminating the risk of potential errors during learning that could affect fragile neonates.


Assuntos
Alimentação com Mamadeira , Competência Clínica , Recém-Nascido Prematuro , Patologia da Fala e Linguagem , Humanos , Patologia da Fala e Linguagem/educação , Recém-Nascido , Feminino , Masculino , Emoções , Educação de Pós-Graduação/métodos , Adulto , Treinamento por Simulação/métodos , Adulto Jovem , Sinais (Psicologia) , Ansiedade/psicologia , Ansiedade/prevenção & controle
2.
Am J Speech Lang Pathol ; 32(6): 2703-2717, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37707357

RESUMO

PURPOSE: Learning experiences that incorporate cadaver prosection or dissection of the brain have shown to enhance the acquisition and retention of neuroanatomy and improve standardized examination scores when included within medical curriculum. However, the role of cadaver-based instruction within allied health fields, and particularly in the field of communication sciences and disorders (CSD), remains limited and less understood. METHOD: The effectiveness of a cadaver-based lab compared to lecture to teach neuroanatomy within an undergraduate/postbaccalaureate clinical neuroscience course for CSD majors was explored within a crossover design. Fifty-four participants were stratified by class rank between two initial training sessions: lab-first versus lecture-first. Neuroanatomical knowledge was tested via labeling tasks at baseline, after the first allocated training, and at 1-week follow-up after crossover training had been completed. RESULTS: Both cohorts demonstrated significant gains in neuroanatomical knowledge following training, yet after the initial training session, students that received cadaver-based instruction produced a significantly greater number (p < .001) and more accurate (p < .001) anatomical labels than students that received lecture. After completion of the crossover design, students receiving cadaver-based instruction prior to lecture continued to demonstrate superior labeling accuracy at follow-up testing (p = .022). CONCLUSIONS: Cadaver-based instruction was more effective in improving students' ability to identify neuroanatomy compared to lecture for CSD students. Interestingly, cadaver-based demonstrations were also most effective in bolstering students' retention of structural knowledge when conducted before, instead of after, a lecture. Clinical training programs, specifically student learning outcomes, benefit from cadaver-based instruction that provides both three-dimensional orientation and a deep appreciation of the human elements of clinical anatomy. Furthermore, both the acquisition and retention of anatomical concepts may be enhanced through strategic instructional design, particularly in regard to the order of lecture and lab experiences.


Assuntos
Instrução por Computador , Neuroanatomia , Humanos , Cadáver , Currículo , Dissecação/educação , Avaliação Educacional , Aprendizagem , Neuroanatomia/educação , Estudos Cross-Over
3.
Laryngoscope ; 133(6): 1434-1441, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36062957

RESUMO

OBJECTIVE: Voluntary cough testing (VCT) may be useful for determining aspiration risk in neurogenic dysphagia; however, has yet to be investigated in traumatic cervical spinal cord injury (tCSCI). The study explored if VCT may elucidate swallowing safety and kinematics related to airway protection in tCSCI survivors. METHODS: Ten inpatients, 13-73 days post-tCSCI (7 incomplete injuries), completed VCT and a modified barium swallowing study that was analyzed via the Penetration Aspiration Scale (PAS) and norm-referenced measures of swallowing events related to airway protection. Spearman rho correlations explored relations among cough airflow, median PAS, and airway protection. Mann-Whitney U tests explored group differences based on clinical airway invasion (PAS > 2) and receiver operating characteristic statistics probed the sensitivity/specificity of VCT measures. RESULTS: Safe (PAS > 2) and unsafe swallowers differed by cough volume acceleration (CVA) for the total sample and by inspiratory duration for incomplete injuries (p = 0.03, r > 0.7). A cut-off value of 24.8 L/s for CVA predicted airway invasion (AUC = 0.917, p = 0.03) with sensitivity = 100%/specificity = 75%. CVA correlated with delayed laryngeal vestibule closure during swallowing for both the total sample and for incomplete injuries (rs  > 0.6, p < 0.05). Blunted peak flow and prolonged cough phases were associated with disordered laryngeal kinematics and prolonged bolus transit during swallowing (p < 0.05). CONCLUSIONS: Reduced CVA, blunted peak flow, and prolonged cough phases reflected PAS and disrupted mechanisms of airway protection in tCSCI survivors, demonstrating promise for VCT as a clinical assessment for post-tCSCI dysphagia. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:1434-1441, 2023.


Assuntos
Medula Cervical , Transtornos de Deglutição , Laringe , Humanos , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Tosse/etiologia , Medula Cervical/lesões , Deglutição
4.
Dysphagia ; 37(6): 1599-1611, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35212848

RESUMO

Videofluoroscopic analyses of swallowing in survivors of traumatic cervical spinal cord injury (tCSCI) have been largely limited to case reports/series and qualitative observations. To elucidate the disrupted physiology specifically underlying dysphagia post-tCSCI, this prospective observational study analyzed videofluoroscopic swallow studies (recorded at 30 frames per second) across 20 tCSCI survivors. Norm-referenced measures of swallow timing or displacement, and calibrated area measures of laryngeal vestibule closure (LVC) were explored in relation to the severity of aspiration or pharyngeal residue. Videofluoroscopic performance was compared by injury level, surgical intervention, tracheostomy status, and in relation to clinical bedside assessments. Reduced pharyngeal constriction, delayed hyoid elevation, and impaired LVC characterized post-tCSCI dysphagia. Reduced extent of hyoid excursion and of pharyngoesophageal segment (PES) opening were not as prominent, only present in approximately half or less of the sample. Ten participants aspirated and 94% of aspiration events were silent. Severity of aspiration significantly correlated with pharyngeal constriction and prolonged pharyngeal transit times. Post-swallow residue correlated with delayed PES distention/closure and prolonged pharyngeal transit. Clinical inference regarding the integrity of the pharyngeal phase at bedside was limited; however, EAT-10 scores demonstrated promise as an adjuvant clinical marker of post-tCSCI dysphagia. This exploratory study further describes the pathophysiology underlying post-tCSCI dysphagia to promote deficit-specific rehabilitation and functional recovery.


Assuntos
Medula Cervical , Transtornos de Deglutição , Laringe , Humanos , Deglutição/fisiologia , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Medula Cervical/diagnóstico por imagem , Medula Cervical/lesões , Cinerradiografia , Laringe/diagnóstico por imagem , Fluoroscopia
5.
Dysphagia ; 37(1): 99-115, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34402968

RESUMO

Measures of tongue strength and endurance using the Iowa Oral Performance Instrument (IOPI) may have diagnostic utility during clinical swallowing evaluations for persons with Parkinson's disease (PwPD). Thus, the objective was to systematically analyze the existing literature comparing IOPI values of tongue strength and endurance between age- and sex-match pairs of PwPD and healthy adults as well as across disease stages. A systematic review of 12 databases and Google Scholar identified five peer-reviewed articles published in English (1990-2019) that compared tongue strength and/or endurance between PwPD and controls. Individual-level data were published in two studies and provided by authors for three studies. Study appraisal included the NIH Quality Assessment Tool and STROBE checklists. Limited data for posterior tongue pressures restricted meta-analyses to anterior pressures. Meta-analyses of group means indicated reduced tongue strength across 106 matched pairs (p < .001, I2 = 0%) and a trend for reduced endurance across 41 matched pairs (p = .07, I2 = 54%). Participant-level analyses found reduced strength (96 pairs, p < .001) and endurance (41 pairs, p = .011) secondary to PD. Tongue strength (n = 68), but not endurance (n = 41), inversely correlated with disease stage when controlling for age (p ≤ .018). Overall, clinicians should be aware that reduced anterior tongue strength and endurance are as follows : expected in approximately one-third and one-fourth of PwPD, respectively, and reduced anterior tongue strength may manifest as early as Hoehn and Yahr stage 2 with continual decline as disease progresses. Further investigation is warranted regarding the relation among tongue strength, tongue endurance, and swallowing physiology as well as applications of tongue pressure training within dysphagia rehabilitation for PwPD.


Assuntos
Transtornos de Deglutição , Doença de Parkinson , Adulto , Deglutição/fisiologia , Transtornos de Deglutição/complicações , Transtornos de Deglutição/etiologia , Humanos , Iowa , Força Muscular/fisiologia , Doença de Parkinson/complicações , Pressão , Língua/fisiologia
6.
Brain Sci ; 11(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671031

RESUMO

Transcranial direct current stimulation (tDCS) may enhance speech and language treatment (SLT) for stroke survivors with aphasia; however, to date, there is no standard protocol for the application of tDCS in post-stroke aphasia. We explored the safety and efficacy of fMRI-guided tDCS on functional language and cortical activity when delivered to the lesioned left hemisphere concurrently with SLT across an extended, six-week treatment period. Twelve persons with chronic, nonfluent aphasia following a single left-hemisphere stroke participated in the three-arm (anodal vs. cathodal vs. sham) single-blind, parallel, pilot trial. No serious adverse events occurred during 30 treatment sessions or in the following six weeks. All groups demonstrated functional language gains following intensive treatment; however, active tDCS resulted in greater gains in standardized, probe, and caregiver-reported measures of functional language than sham. Evidence declaring one polarity as superior for inducing language recovery was mixed. However, cathodal stimulation to the lesioned left hemisphere, expected to have a down-regulating effect, resulted in increased areas of cortical activation across both hemispheres, and specifically perilesionally. Generalization of these preliminary findings is limited; however, results are nevertheless compelling that tDCS combined with SLT can be safely applied across extended durations, with the potential to enhance functional language and cortical activation for persons with aphasia.

7.
Top Stroke Rehabil ; 27(4): 241-250, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31838961

RESUMO

Background: Post-stroke dysphagia is characterized by reduced corticolingual excitability and lingual pressure; however, it remains unknown if transcranial magnetic stimulation (TMS) directly facilitates lingual pressure generation.Objectives: To explore optimal procedures for single pulse TMS using neuronavigation to evoke lingual pressure in intact and disrupted neural networks.Methods: Using co-registered functional magnetic resonance imaging, stimulation sites were determined for five healthy adults (Mage = 67) and four stroke survivors with dysphagia and reduced tongue strength (Mage = 66). Evoked lingual pressures were sampled across 45-65% of maximum stimulator output. Healthy participants repeated TMS with a bite block to isolate lingual pressure from off-target stimulation of mandibular elevators.Results: Only one functionally-guided stimulation site fell within previously reported optimal lateral (8-11cm) and anterior (2-4.25cm) coordinates. Lingual pressure was stable prior to pulse and increased linearly with intensity for both groups (p = .005). Post-stroke active motor thresholds were elevated compared to healthy adults (p = .025). Lingual pressure latency remained stable across intensities (p > .05). Jaw stabilization via bite block reduced the mean magnitude of evoked lingual pressure by approximately 16%.Conclusions: Single pulse TMS directly evokes higher lingual pressure and can define motor thresholds in intact and disordered corticolingual pathways. Stimulation sites using neuronavigation in healthy adults and stroke survivors largely differed from external coordinates in the literature that were predominantly established in young adults. Procedures to investigate motor thresholds for lingual pressure generation are proposed. The therapeutic role of TMS to address post-stroke deficits in lingual pressure and corticolingual excitability warrants continued investigation.


Assuntos
Transtornos de Deglutição/terapia , Potencial Evocado Motor/fisiologia , Imageamento por Ressonância Magnética , Córtex Motor/fisiopatologia , Acidente Vascular Cerebral/terapia , Língua/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Idoso , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Acidente Vascular Cerebral/complicações , Sobreviventes
8.
J Speech Lang Hear Res ; 62(8): 2671-2679, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31390280

RESUMO

Purpose Dysphagia in Parkinson's disease (PD) is a major cause of depression and reduced quality of life (QOL). PD-related dysphagia often involves lingual dysfunction and weak pressure generation. The relation of disordered lingual pressure generation to swallowing-related QOL in persons with PD remains unknown. Method Twenty-four persons with idiopathic PD completed the Swallowing Quality of Life (SWAL-QOL) questionnaire and an evaluation of anterior and posterior tongue strength. Peak pressures were compared to age- and sex-matched controls. The magnitude of and latency to peak pressure were explored in relation to SWAL-QOL scores. Results Persons with PD exhibited significant anterior (p = .019) but not posterior (p = .081) lingual weakness compared to controls. Persons with PD and reduced anterior tongue strength (< 42 kPa) reported lower SWAL-QOL total (p = .043), extended eating durations (p = .025), and a reduced desire to eat (p = .020). Prolonged latency to peak anterior pressure in PD inversely correlated with SWAL-QOL total (r = -.750, p < .001) and served as a significant, independent predictor of 67% of the variance in SWAL-QOL total when controlling for age, sex, and disease stage. Conclusion Overall, SWAL-QOL scores declined in the presence of lingual pressure dysfunction. Lingual weakness and prolonged pressure building patterns secondary to PD, especially of the anterior tongue, may represent clinically relevant disruptions to mealtime behaviors that undermine swallowing-related QOL. These preliminary findings support further investigation of lingual pressure patterns in PD to help identify debilitating dysphagia and develop treatment strategies.


Assuntos
Transtornos de Deglutição/fisiopatologia , Doença de Parkinson/fisiopatologia , Qualidade de Vida , Doenças da Língua/fisiopatologia , Idoso , Estudos de Casos e Controles , Deglutição/fisiologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/psicologia , Feminino , Humanos , Masculino , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Pressão , Inquéritos e Questionários , Língua/fisiopatologia , Doenças da Língua/etiologia , Doenças da Língua/psicologia
9.
Am J Speech Lang Pathol ; 28(3): 1268-1274, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31335179

RESUMO

Purpose Dysphagia treatments to address the deterioration of oropharyngeal and respiratory functions in Parkinson's disease (PD) are few and rarely researched in persons with complex medical histories. This research note explored the effects of an intensive exercise-based swallowing program (ISP) that incorporated lingual and respiratory exercises for persons with PD and complex medical history. Method A single-case experiment was conducted across a 4-week ISP of lingual training and expiratory muscle strengthening for 2 participants (67-year-old man and 61-year-old woman). Probes included tongue strength and maximum expiratory pressure. Generalization measures included the Mann Assessment of Swallowing Ability (Mann, 2002), Timed Water Test (Hughes & Wiles, 1996), Repetitive Saliva Swallow Test (Oguchi et al., 2000), Functional Oral Intake Scale (Crary, Carnaby Mann, & Groher, 2005), and Swallowing Quality of Life questionnaire (McHorney et al., 2002). Results Gains occurred in tongue strength and maximum expiratory pressure (p ≤ .002) with large effect sizes (d ≥ 1.3) as well as Mann Assessment of Swallowing Ability and Timed Water Test performance. Repetitive Saliva Swallow Test performance and Functional Oral Intake Scale improved for 1 participant, whereas the other maintained function. Swallowing Quality of Life questionnaire remained largely unchanged; however, participants indicated they became more aware of their swallowing difficulties at posttreatment. Conclusions Persons with PD and complex medical history demonstrated increased lingual and expiratory muscle strength following a brief intensive program, which further generalized to select clinical swallowing measures. Findings suggest an overall positive and potentially additive or synergistic effect of an ISP. Future research may refine optimal candidacy and regimens for ISPs, which may help to maximize clinically meaningful returns, especially considering the increased demands of an intensive program.


Assuntos
Transtornos de Deglutição/reabilitação , Terapia por Exercício/métodos , Doença de Parkinson/reabilitação , Idoso , Deglutição/fisiologia , Transtornos de Deglutição/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Qualidade de Vida , Estudos de Caso Único como Assunto , Resultado do Tratamento
10.
J Speech Lang Hear Res ; 61(2): 257-265, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29396576

RESUMO

Purpose: Swallowing impairment, or dysphagia, is a known contributor to reduced quality of life, pneumonia, and mortality in Parkinson's disease (PD). However, the contribution of tongue dysfunction, specifically inadequate pressure generation, to dysphagia in PD remains unclear. Our purpose was to determine whether lingual pressures in PD are (a) reduced, (b) reflect medication state, or are (c) consistent with self-reported diet and swallowing function. Method: Twenty-eight persons with idiopathic PD (PwPD) and 28 age- and sex-matched controls completed lingual pressure tasks with the Iowa Oral Performance Instrument. PwPD were tested during practically defined ON and OFF dopaminergic medication states. Participants were also stratified into three sex- and age-matched cohorts (7 men, 5 women): (a) controls, (b) PwPD without self-reported dysphagia symptoms or diet restrictions, and (c) PwPD with self-reported dysphagia symptoms with or without diet restrictions. Results: PwPD exhibited reduced tongue strength and used elevated proportions of tongue strength during swallowing compared with controls (p < .05) without an effect of medication state (p > .05). Reduced tongue strength distinguished PwPD with self-reported dysphagia symptoms from PwPD without reported symptoms or diet restrictions (p = .045) and controls (p = .002). Conclusion: Tongue strength was significantly reduced in PwPD and did not differ by medication state. Tongue strength differentiated between PwPD with and without self-reported swallowing symptoms. Therefore, measures of tongue strength and swallowing pressures may serve as clinical indicators for further dysphagia evaluation and may promote early diagnosis and management of dysphagia in PD.


Assuntos
Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Força Muscular , Doença de Parkinson/fisiopatologia , Língua/fisiopatologia , Idoso , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Fenômenos Biomecânicos , Estudos de Coortes , Transtornos de Deglutição/etiologia , Dieta , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Doença de Parkinson/tratamento farmacológico , Pressão , Autorrelato
11.
Int J Speech Lang Pathol ; 20(2): 274-283, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28425326

RESUMO

PURPOSE: Evaluation of the Naming and Oral Reading for Language in Aphasia 6-point scale (NORLA-6), a scoring system of oral reading and naming performance in aphasia. METHOD: Data were drawn from 91 participants with non-fluent aphasia secondary to left-hemisphere stroke across four treatment studies. To assess validity, Spearman's correlations were calculated between the NORLA-6 and the Gray Oral Reading Test-Fourth Edition (GORT-4) Accuracy score, GORT-4 Rate score and the Boston Naming Test (BNT). Inter-rater and test-retest reliability were evaluated using correlations. Sensitivity to change following oral reading intervention was analysed using Wilcoxon Signed Rank tests between pre- and post-treatment NORLA-6 scores. RESULT: NORLA-6 performance was significantly correlated (p < 0.001) with all reference tests (GORT-4 Accuracy, rs=0.84; GORT-4 Rate, rs= 0.61; and BNT, rs= 0.92). Inter-rater (ICC ≥0.90) and test-retest (r > 0.92) reliability were both excellent. Sensitivity following oral reading intervention was demonstrated in both oral reading accuracy and rate (p < 0.004). CONCLUSION: The NORLA-6 is a valid and reliable measure of oral reading and naming performance. It also demonstrates sensitivity to change in treatment-targeted behaviours. Therefore, the NORLA-6 scale may enhance outcome measurement in both clinical practice and aphasia research.


Assuntos
Afasia/diagnóstico , Testes de Linguagem , Patologia da Fala e Linguagem/métodos , Adulto , Idoso , Afasia/etiologia , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Leitura , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Acidente Vascular Cerebral/complicações , Adulto Jovem
12.
Dysphagia ; 32(6): 759-766, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28687869

RESUMO

Tongue strength is routinely evaluated in clinical swallowing evaluations since lingual weakness is an established contributor to dysphagia. Tongue strength may be clinically quantified by the maximum isometric tongue pressure (MIP) generated by the tongue against the palate; however, wide ranges in normal performance remain to be fully explained. Although orthodontic theory has long suggested a relation between lingual function and oral cavity dimensions, little attention has been given to the potential influence of oral and palatal structure(s) on healthy variance in MIP generation. Therefore, anterior and posterior tongue strength measures and oropalatal dimensions were obtained across 147 healthy adults (aged 18-88 years). Age was confirmed as a significant, independent predictor explaining approximately 10.2% of the variance in anterior tongue strength, but not a significant predictor of posterior tongue strength. However, oropalatal dimensions predicted anterior tongue strength with over three times the predictive power of age alone (p < .001). Significant models for anterior tongue strength (R 2 = .457) and posterior tongue strength (R 2 = .283) included a combination of demographic predictors (i.e., age and/or gender) and oropalatal dimensions. Palatal width, estimated tongue volume, and gender were significant predictors of posterior tongue strength (p < .001). Therefore, oropalatal dimensions may warrant consideration when accurately differentiating between pathological lingual weakness and healthy individual difference.


Assuntos
Deglutição/fisiologia , Língua/anatomia & histologia , Língua/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Pressão , Adulto Jovem
13.
Science ; 318(5857): 1777-9, 2007 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-18079403

RESUMO

RNA polymerase II (Pol II) transcribes genes that encode proteins and noncoding small nuclear RNAs (snRNAs). The carboxyl-terminal repeat domain (CTD) of the largest subunit of mammalian RNA Pol II, comprising tandem repeats of the heptapeptide consensus Tyr1-Ser2-Pro3-Thr4-Ser5-Pro6-Ser7, is required for expression of both gene types. We show that mutation of serine-7 to alanine causes a specific defect in snRNA gene expression. We also present evidence that phosphorylation of serine-7 facilitates interaction with the snRNA gene-specific Integrator complex. These findings assign a biological function to this amino acid and highlight a gene type-specific requirement for a residue within the CTD heptapeptide, supporting the existence of a CTD code.


Assuntos
Regulação da Expressão Gênica , RNA Polimerase II/metabolismo , RNA Nuclear Pequeno/genética , Serina/metabolismo , Transcrição Gênica , Alanina , Sequência de Aminoácidos , Linhagem Celular , Sequência Consenso , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Mutação , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Fosforilação , Estrutura Terciária de Proteína , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Polimerase II/química , RNA Polimerase II/genética , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Moldes Genéticos
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